Alkali metal salt of propargyl hydrogensulfuric acid and process of making unsaturated cellulose ether textiles



ALKALI METAL SALT F PROPARGYL HYDRO- GENSULFURIC ACID AND PRQCESS 0F MAK- ING UNSATURATED CELLULOSE ETHER TEX- TILES Edvwin D. Parker and John D. Guthrie, New Orleans, La., assiguors to the United States of America as represented by the Secretary of Agriculture N0 Drawing. Application July 14, 1952, Serial No. 298,880

2 Claims. (Cl. 8120) (Granted under Title 35, U. S. Code (1952), see. 266) A non-exclusive, irrevocable, royalty-free license in the invention herein described, for all governmental purposes, throughout the world, with the power to grant sublicenses for such purposes, is hereby granted to the Governement of the United States of America.

This invention relates to partial etherification of cellulose textile fibers, especially cotton fabrics in which the properties of hand, feel, tensile strength, and the like characteristics of the cotton fabric are not materially altered. More particularly the invention provides propargylating agents with which cellulose textile fibers can be etherified using conventional cotton textile processing apparatus, and provides a process for the production of propargyl or alkenyl ethers of the cellulose textile fibers.

The cellulose textile fibers can be etherified by the process of this invention before, during, or after the processing of the fibers into threads, fabrics, or the like.

The propargylating agents are the alkali metal salts of propargyl hydrogensulfuric acid, particularly the sodium or potassium salts. These salts are miscible with water solutions of sodium hydroxide of mercerizing strength. When dissolved in water along with unreacted sodium hydroxide they react with the cellulose fibers to form fibrous unsaturated partial ethers of cellulose in which the unsaturated groups are propargyl radicals or polymers thereof.

The preferred alkenylating agents used for producing the alkenyl ethers of the cellulose fibers are the sodium and potassium salts of allylic alkenyl hydrogensulfuric acids which salts are soluble in aqueous alkali metal hydroxide, typified by the sodium salt of allyl hydrogensulfuric acid. The alkenylating agents can be produced by a variety of methods including the use of the appropriate alkenol in the method of preparingthe propargylating agents.

In the production of the unsaturated partial ethers of the cellulose textile fibers in accordance with the invention the alkali metal salt of the propargyl or allyl hydrogensulfuric acid is preferably dissolved in aqueous alkali metal hydroxide, sodium hydroxide being preferred, of mercerizing strength to form a solution containing from about to percent of the propargyl or allyl hydrogensulfuric acid anions. The cellulose textile fibers, preferably a cotton fabric, are impregnated with the resultant solution and cured by heating at a temperature of from about 80 to 120 C. for at least from about 30 to 90 minutes, using a longer time with a lower temperature. The cured material is then washed, preferably with water. Where a high degree of substitution is desired the impregnation and curing is preferably repeated a number of times. Alternatively, a relatively high degree of substitution can be obtained from a single impregnation by wetting the cured impregnated material with water and recuring the wet material.

The unsaturated ethers thus produced may be converted to derivatives of the ethers by contacting them nitcd States Patent 0 with a reagent which will add to an aliphatic carbon to carbon unsaturated linkage, such as chlorine or bromine in a solvent or as released in a solution in contact with the unsaturated ether. Preferred reagents include carbon tetrachloride solutions of bromine, aqueous solutions of sodium hypochlorite in the presence of an acid, and the like solutions.

The combustibility of a cotton fabric is reduced, in general, by impregnating the cotton, in which the cellulose has been etherified and brominated in the manner described above, with an aqueous solution containing cations of a polyvalent metal having an easily reducible oxide.

Preferred polyvalent metals include ferric chloride and antimony trichloride.

The following Example I exhibits the invention for producing the alkali metal salt of propargyl hydrogensulfuric acid.

Example I One mole of chlorosulfonic acid was added to a vigorously stirred mixture of 2.2 moles of pyridine and an equal volume of carbon tetrachloride at about 0 C. The addition was made slowly in a dropwise manner. Pyridinium chlorosulfonate formed as a cake on the surface of the flask and as a solid dispersed in the liquid.

One mole of propargyl alcohol was slowly added to this mixture at about 0 C. The mixture was agitated while the temperature was allowed to rise to about room temperature. Substantially all of the pyridinium chlorosulfonate disappeared. Enough water was then added to cause the separation of two clearly defined liquid phases. The aqueous phase was further diluted with water until it would react and release carbon dioxide upon the addition of anhydrous sodium carbonate. The addition of the carbonate was continued with agitation until the evolution of carbon dioxide had stopped. The resultant solution was cooled to about 10 C. and the solids were filtered 01?. Sodium propargyl sulfate (the sodium salt of propargyl hydrogensulfuric acid) was separated from these solids by extraction with warm ethanol and was recrystallized from the same alcohol.

The following Examples 11, III, IV and VI exhibit the production of allyl ethers of cellulose textile fibers.

Example 11 1.5 grams of sodium allyl sulfate (the sodium salt of allyl hydrogensulfuric acid) was dissolved in 15 ml. of 14% sodium hydroxide solution and padded on a 5 x 12 in. piece of 80 sq. cotton fabric weighing 4.2 grams. The pickup of solution was 8.2 grams. The impregnated fabric was cured at C. for 30 minute intervals with of the fabric being removed at each successive interval. Thus 3 samples were obtained with curing times of /2, 1, and 1 /2 hours. Each of the cured samples was thoroughly washed with tap water and-dried to equilibrium atroom conditions.

Bromine absorption of the treated samples indicated a degree of substitution of 0.046 for the /2 hour cured sample and 0.061 for the 1 hour cured sample, and 0.073 for the 1 /2 hour cured sample.

In an analogous experiment using 3 g. of sodium allyl sulfate in 15 ml. of 16% sodium hydroxide solution the degree of substitution was 0.070'for the /2 hour curing, 0.084 for the 1 hour curing, and 0.098 for the 1 /2 hour curing.

Example III 5 g. of sodiumallyl sulfate was dissolved in 50 ml. of 16% sodium hydroxide solution and employed in an analogous treatmentof 80 sq. cotton fabric. These samples were cured at C. for 1 /2 hours. The first of these samples wasset aside and the other 2 were reimpregnated and cured with impregnating solutions of the same concentration. Sample 3 was reimpregnated a third time in the same way.

The first of these samples had a degree of substitution of 0.097, the second of 0.165, and the third of .241.

Example I V Two samples of 80 sq. cotton fabric were impregnated and cured in the above manner with a solution of 4 g. of sodium allyl sulfate in 40 ml. of 16% sodium hydroxide solution. Both samples were cured at 110 C. for four -minute intervals. (A total curing time of 16 minutes.) Both samples were removed at the end of each interval, and the first sample was wet by spraying it with a fine spray of water. After so wetting sample 1, both samples were returned to the oven for the next 15 minute curing interval. This procedure was repeated for two more curing intervals. After the last interval both samples were thoroughly washed with running tap water and air dried to equilibrium.

Bromine absorption indicated a degree of substitution of 0.118 for sample 1 (cured with rewetting) and 0.092 for sample 2 (cured dry).

The following Example V exhibits the production of the propargyl ether of cellulose textile fibers.

Example V 6 g. of sodium propargyl sulfate was dissolved in 40 ml. of 16% sodium hydroxide solution and padded on 3 samples of 80 sq. cotton fabric. The samples were cured at 100 C. for 1 hour and washed with running tap water and oven dried and then were equilibriated. The sample weights before and after treatment were: Sample 1, 7.52 g. and 8.08 g.; sample 2,. 7.41 g. and 7.97 g.; sample 3,

7.43 g. and 8.03 g. Samples 2 and 3 were retreated in the same manner. After equilibriating sample 2 weighed 8.37 g.

Sample 3 was retreated a third time. After equilibration the sample weighed 8.79 g.

The degrees of substitution calculated on the basis of bromine absorption and on the basis of weight increase respectively were: Sample 1, 0.050 and 0.307; sample 2, 0.088 and 0.529; sample 3, 0.1124 and 0.787. The wide discrepancy indicates substitution by polymers of the propargyl group.

These samples exhibit crease resistance. The following data was obtained on a Monsanto wrinkle recovery tester. A mercerized control showed a recovery of 27% Sample 1 showed a recovery of 38%, sample 2 of 53%, and sample 3 of 45%.

Example VI A, solution of 450 g. of sodium hydroxide, 300 g. of sodium allyl sulfate, and 2250 g. of water was placed in a padder. A 19. in. wide strip of 80 sq. cotton fabric, 20,y.ds; long. (990 g.), was padded with the solution and picked up. 1160 g. of liquid. The fabric was cured at 110 C. for; 1 hour.- It was then wet and washed with water on a jig. This was followed with one wash with cold water, 3 washes with hot water, onc rinse with an acetic acid sour followed by water washing until the wash was neutral. The fabric was then centrifuged to remove the excess water and was dried on a tenter frame.

Five yards of the fabric was removed and designated as single treated sample. The remaining fabric was retreated, 700 g. of fabric being used and picking up 880 g. of liquid. The retreated fabric was cured, washed, and dried in the; above manner.

A second five-yard sample was removed and designated as double treated sample. Theremaining 10 yards was treated a third time in the above manner, 435 g. of fabric being used and 485 g. of liquid beingpicked-up.

The degree of substitution indicated the bromine absorption was 0.067 for the single treated sample, 0.137 for the double treated sample, and 0.173 for" thetriple treated sample.

4 The. following Examples VII, VH1 and. IX exhibit. the production of halogenated derivatives of the cellulose ethers.

Example VI] A sample of the triple treated fabric prepared in Example VI was covered with glacial acetic acid containing an excess of chlorine and allowed to stand at room temperature with occasional shaking for 5 hours. The sample was thoroughly washed with distilled water and allowed to stand 1 hour in an 0.1 normal solution of sodium thiosulfate, washed again with distilled water and air dried.

The dried chlorinated sample contained 3.94% chlonne.

A sample of the same fabric was placed in a flask and covered with 365 ml. of water containing 25 ml. of glacial acetic acid. 135 ml. sodium hypochlorite solution (containing 5.25% sodium hypochlorite by weight) was added in small portions with shaking. After standing 3 hours the above fabric was removed from the solution, washed 8 times with distilled water, and dried to equilibrium in air. It weighed 17.8 g. and contained 3.83% chlorine on a dry basis.

Example VIII A sample of the triple treated fabric prepared in Example VI, weighing 51.6 grams, was covered with 750 ml. of acetic acid and 3 ml. of bromine was added. The vessel containing the liquids and fabric was allowed to stand at room temperature for 4 hours with occasional shaking. The fabric was washed with first cold then hot tap water and was air dried to equilibrium. It weighed 58.1 g. and contained 12.82% bromine on a dry basis.

Example IX A sample of the triple treated fabric of Example VI, weighing 17.5 g., was covered with a solution prepared in the following manner. 3 ml. of bromine was dissolved in 400 ml. of ice cooled water and added dropwise to a vigorously stirred ice cold solution of 5.6 g. of sodium hydroxide in 200 ml. of water. Acetic acid was added to the solution surrounding the fabric until the color of bromine began to appear. The solution was allowed to stand for 2 hours at about 0 degrees C. and for about 1 hour at room temperature. The fabric was removed, washed with distilled water and after drying to equilibrium in air it weighed 19.3 g. and contained 8.75% bromine.

The following Examples X' and XI exhibit a process for reducing the combustibility of a cotton fabric.

Example X A sample of the triple treated cotton fabric in which the cellulose had. been converted to an allyl ether by the process of; Example VI was bromina'ted by the process of Example VIII. It was then soaked in a 5% solution of FeCls.6H2O in water for 20 minutes and then placed in a 2% aqueous solution of sodium hydroxide for 10 minutes; Afterwashing and drying the fabric would not support combustion when it was held in a vertical position and" lighted at the bottom.

A similar application of FeCls.6I-I2O to untreated fabric, to control fabric processed with sodium hydroxide solution only, or to allylated fabric that had not been brominated produced a fabric that burned readily. The brominated allylated fabric also burned readily prior to application of FeCl3.6H2O.

Example XI A similar brominated allyl cotton fabric was soaked for 20 minutes in an aqueous" solution containing 5 g. of antimonytrichlorideand 20ml. of concentrated hydrochloric acid in ml. of water; When water Washed" and dried the fabric would'not support combustion when held in a vertical position and lighted at the bottom.

A similar application of antimony trichloride to untreated fabric, to control fabric processed with sodium hydroxide only or to allylated fabric that had not been brominated produced a fabric that burned readily. The brominated allylated fabric also burned readily prior to application of antimony trichloride.

We claim:

1. An alkali metal salt of propargyl hydrogensulfuric acid.

2. A process of producing a fibrous ether of cellulose textile fibers comprising impregnating cellulose textile fibers with an aqueous alkali metal hydroxide of mercerizing strength containing from 5 to by weight of the anions of an alkali metal salt of an acid selected from the group consisting of propargyl hydrogensulfuric acid and allyl hydrogensulfuric acid, and heating the impregnated fibers at a temperature of about from 80 to 120 C. for at least about from to minutes, using a longer time with a lower temperature.

References Cited in the file of this patent UNITED STATES PATENTS 

1. AN ALKALI METAL SALT OF PROPARGYL HYDROGENSULFURIC ACID.
 2. A PROCESS OF PRODUCING A FIBROUS ETHER OF CELLULOSE TEXTILE FIBERS COMPRISING IMPREGNATING CELLULOSE TEXTILE FIBERS WITH AN AQUEOUS ALKALI METAL HYDROXIDE OF MERCERIZING STRENGTH CONTAINING FROM 5 TO 15% BY WEIGHT OF THE ANIONS OF AN ALKALI METAL SALT OF AN ACID SELECTED FROM THE GROUP CONSISTING OF PROPARGYL HYDROGENSULFURIC ACID AND ALLYL HYDROGENSULFURIC ACID, AND HEATING THE IMPREGNATED FIBERS AT A TEMPERATURE OF ABOUT FROM 80 TO 120* C. FOR AT LEAST ABOUT FROM 30 TO 80 MINUTES, USING A LONGER TIME WITH A LOWER TEMPERATURE. 